Peking Univ, Sch Phys, Beijing 100871, Peoples R China
; Zhejiang Univ, Dept Phys, Hangzhou 310027, Peoples R China
; Peking Univ, Coll Life Sci, Dept Cell Biol & Genet, Beijing 100871, Peoples R China
; Acad Sinica, Inst High Energy Phys, Beijing 100039, Peoples R China
Cell-free system is interesting and useful for studying nuclear assembly in mitosis. Atomic force microscopy (AFM), which is a simple way for imaging fixed reassemble nuclei with high resolution, has not been used in the cell-free system. In this paper, we put forward an air-drying sample preparation for AFM. Using AFM, we observed nuclear reassembly process within 100 nm resolution in a cell-free system. As a result, we found that the images were artifact-free, and with higher resolution compared with fluorescent optical microscope images. Furthermore, the morphology of membrane vesicles was obtained clearly, and a dynamic change of morphology during the vesicles' approaching to nuclear envelope was also observed, which is enlightened to understand the mechanism of nuclear envelope assembly.